 /*******************************************************************************
  * Copyright (c) 2003, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.progress;

 import org.eclipse.swt.graphics.Image;

 /**
  * The JobTreeElement is the abstract superclass of items
  * displayed in the tree.
  */
 abstract class JobTreeElement implements Comparable {

     /**
      * Return the parent of this object.
      * @return Object
      */
     abstract Object getParent();

     /**
      * Return whether or not the receiver has children.
      * @return boolean
      */
     abstract boolean hasChildren();

     /**
      * Return the children of the receiver.
      * @return Object[]
      */
     abstract Object [] getChildren();

     /**
      * Return the displayString for the receiver.
      * @return String
      */
     abstract String getDisplayString();
     
     /**
      * Return the displayString for the receiver.
      * @param showProgress Whether or not progress is being
      * shown (if relevant).
      * @return String
      */
     String getDisplayString(boolean showProgress){
         return getDisplayString();
     }

     /**
      * Get the image for the reciever. By default there is no image.
      * @return Image or <code>null</code>.
      */
     public Image getDisplayImage() {
         return null;
     }

     /**
      * Return the condensed version of the display string
      * @return String
      */
     String getCondensedDisplayString() {
         return getDisplayString();
     }

     /**
      * Return whether or not the receiver is an info.
      * @return boolean
      */
     abstract boolean isJobInfo();

     /* (non-Javadoc)
      * @see java.lang.Comparable#compareTo(java.lang.Object)
      */
     public int compareTo(Object arg0) {
         return getDisplayString().compareTo(
                 ((JobTreeElement) arg0).getDisplayString());
     }

     /**
      * Return whether or not this is currently active.
      * @return boolean
      */
     abstract boolean isActive();

     /**
      * Return whether or not the receiver can be cancelled.
      * @return boolean
      */
     public boolean isCancellable() {
         return false;
     }

     /**
      * Cancel the receiver.
      */
     public void cancel() {
         //By default do nothing.
 }
 }

